SU550556A1 - A device for measuring the physical and mechanical parameters of an object - Google Patents

Description

the torus reinforces the object under study 2, the control generator 3 with frequency sweep, vibration: converter 4 installed on the platform of the shaker, vibrator 5, mounted on the object under study, matching amplifiers 6 and 7 connected to the inputs of the phase detector 8, output which is connected to the control input of the electronic key 9, the television meter 10 of the geometric parameters of an object, the frequency discriminator 11, the memory block 12, the outputs of which are connected to the inputs of the multiplication unit 13, the output of which is through quadra The torus 14 is connected to the indicator 15, the control unit 16.

The device works as follows.

The object under study 2, mounted on the platform of the vibrostand 1, is projected onto the television meter screen 10 geometric dimensions of the object, from which the voltage is removed, proportional to the diameter of the object under study. This voltage is stored in one channel of memory unit 12. After measuring the diameter of the object under study, the vibrostand is excited by the voltage of a constant level of the control generator, which performs a frequency sweep, which ensures a constant disturbing force in a wide range of frequencies acting on the object under study. . The vibrations of the vibrostand excite the object under study, the vibrations of which are converted by means of the vibrator 5 into an electrical signal. This signal through the matching amplifier 6 is fed to one of the inputs of the phase detector 8. To the other input of the phase detector, a signal from the vibrator 4 is amplified, amplified by the matching amplifier 7. When the vibrator platform vibrates at a frequency offset from the resonant frequency of the object under study, the signals at the inputs of the phase detector 8 have the same phase. At the output of the phase detector, a zero level is formed, closing the electronic key 9.

At the moment of resonance of the object under study, which is a system with distributed parameters, a certain phase shift is observed, for example by 90 °, between the acceleration of the object under study at the observation point (voltage from the vibration transducer 5) and the power disturbance generated by the vibration platform platform (voltage from the vibration transducer 4 ). In this case, a voltage is generated at the output of the phase detector 8, which opens the electronic key 9 and stops the frequency control of the control generator 3. The voltage from the output of the frequency discriminator 11, which is proportional to the resonance frequency of the object under study, enters through the electronic key 9 into the memory block 12. Simultaneously with the voltage from the output of the phase detector 8, the memory block 12 switches to the read mode. With this

one output of the memory block is taken a signal,: the level of which is proportional to the diameter of the object under study 2, and from the other output - the voltage level proportional to the resonant frequency of the object under study. The signals are fed to the inputs of multiplier 13, which multiplies the analog signals and converts the product into a number of pulses. At the output of the multiplying unit, a pulse signal is formed, with the number of pulses proportional to the product of the diameter of the object and the resonant frequency. These pulses come

to the input of the quad 14, at the output of which a square of a number is allocated proportional to the hardness of the object. The multiplication of this number, and the scale factor is carried out by the indicator 15, on the digital scoreboard which

A digital indicator of the hardness of the object is displayed.

The multiplier 13 and quad 14 can be performed on sweep type generators with linear and quadratic sweeps.

Thus, the device allows you to automatically and quickly measure the hardness of an object, such as fruits and vegetables, and also to spoil damaged or poor quality fruits with high efficiency.

Claims (2)

1.Dikarev L.A. and Pszchechenkov K.A. “Application of non-destructive testing methods for assessing the quality of fruits and vegetables. Agriculture abroad. Plant growing, 1973, No. 10, p. 20. 2. Author's certificate No. 513266, M. Kl.2 A 01G 7/00, 1974 (prototype).